Nonrepeat attachment for punch presses and the like



Aug. 11, 19 6- E. SCHUESSLER 2 NONREPEAT ATTACHMENT FOR PUNCH PRESSES AND THE LIKE Filed Jan. 22, 1935 Patented Aug. 11, 1936 UNET STATES NONREPEAT ATTACHMENT FOR PUNCH PRESSES AND THE LIKE Emil Schuessler, Buffalo, N. Y.

Application January 22, 1935, Serial No. 2,903

4 Claims.

This invention relates to a non-repeat attachment for punch presses and the like and more particularly to such an attachment which is adapted to be provided on punch presses which are unequipped with a non-repeat clutch so that after the attachment is in operation the operator upon depressing the treadle will effect but a single operation of the punch press after which he must deliberately release the treadle before he can again operate the press. By this means the press is much safer to operate inasmuch as there can be no unexpected operation of the press with the possible injury to the operator.

The principal object of the present invention is to provide an attachment which is simple and inexpensive'in construction and can be easily applied to any type of punch press or like machine so as to increase the factor of safety.

Another purpose of the present invention is to provide such an attachment which is entirely reliable in its operation and in which there is no danger of a failure of the attachment, such failures being doubly dangerous as they are entirely unexpected.

.A further aim of the present invention is to provide such an attachment which is conveniently adjustable and is'compact in construction and is also located out of the work zone so as to not" interfere in any way with the normal use of the press and also is so located'as to not interfere with the adjustment or repair of any other parts of the press.

Another aimis to provide such an attachment which will operate efiiciently and will not get out of adjustment or require repair for a long period of time.

In the accompanying drawing:

Fig. 1 is a perspective View of a punch press showing my non-repeat attachment applied thereto.

Fig. 2 is a vertical, side elevation of my attachment showing it applied to the punch press shown in Fig. 1.

Fig. 3 is a vertical section, taken generally on line 3--3, Fig. 2.

Fig. 4 is a view similar to Fig. 3 showing another position of the parts.

Fig. 5 is a cross section, taken on line 5-5, Fig. 2.

Fig. 6 is a perspective view of the pawl or detent forming a part of the attachment.

The attachment made in accordance with my invention can be applied to punch presses or like machines of any form and is shown in Fig. 1 as applied to a punch press comprising a frame l mounted on a base H and carrying a bed E2 on which the work is placed. The work is operated upon by tools carried by a slide 13 which is reciprocated by an eccentric i4 around an eccentric [-5. The eccentric i is mounted on a main horizontal drive shaft I6, this shaft being journalled in bearings l'l formed in the upper part of the frame It). A pulley I8 is loosely mounted on the drive shaft l6 and is thrown into and out of engagement with the drive shaft by a clutch indicated generally at I 9. This clutch is operated by a rod which, for the purposes of the present invention, is cut into two sections 2% and 26 The lower end of this rod is connected to a treadle 2| which is pivoted at its rear end to the base I l of the frame, as indicated at 22. The treadle 2| is normally held elevated by a spring 23.

With the punch press shown, when not equipped with the non-repeat attachment forming my invention, the operator steps upon the treadle 2| thereby drawing the rod 20*, 29 downwardly, which movement of the rod closes the clutch so that the rotating pulley couples with the main drive shaft l6 and rotates the eccentric I5 so as to reciprocate the slide I3. provision to prevent it the slide l3 will, of course, continue to reciprocate as long as the operator keeps the treadle depressed. In the event that the operator does not remove his foot from the treadle in time a second reciprocation may be unexpected and an injury of serious nature may result. It is to guard against such injuries that the present invention is intended and the attachment embodying the present invention is interposed between the two sections 20 and 20 of the treadle rod so as to prevent a repeated operation of the press until the operator deliberately releases and again depresses the treadle.

As previously stated the shipper rod, with which all presses of this character are equipped, is cut into two sections, 26 and 25 and my attachment is interposed between these two sections. The attachment includes a bracket 25 which is bolted to the side of the frame is so as to guide the lower end of the upper section 20 this bracket a collar 26 is secured to the section 20 and a helical compression spring 21 is interposed between the collar 26 and the bracket 25 so that the upper section 2!] of the shipper rod is yieldingly held in an elevated position in which position the clutch I9 is open so that the pulley l8 rotates freely on the drive shaft !6.

Secured to the lower end of the upper section 20 below the bracket 25 by means of a pin 23 or in any other suitable manner is a sleeve 29 which extends downwardly and at all times encases the upper end of the lower shipper rod section 20 At one side the sleeve 29 is formed to provide a vertical slot 30 which slot registers with a notch 3| provided in the upper end of the lower section 20 On opposite sides of the slot 30 outwardly extending ears 32 are provided" on the sleeve 29, these ears carrying a pin 33. A dog or pawl 34 is pinned or otherwise fastened to the pin 33 and is located between the ears'32 so as to extend through the Above In the absence of slot 30 and be engageable with the notch 3| in the upper end of the lower section 20 of the shipper rod. This dog is normally urged against the side of the lower section 20' of the shipper rod by a small helical compression spring 35 which bears at its upper end against a lug 36 formed integrally with the sleeve 29 and at its lower end against a tailpiece or finger 31 which is fixedly secured to one end of the pin 33, as best illustrated in Figs. 5 and 6.

As the shipper rod sections 2|!"- and 20 are moved downwardly in closing the clutch the tailpiece or finger 31 engages a vertical stop screw 38 which is carried by a bracket 39,'this bracket being suitably secured to the side of the punch press frame Ill, as best illustrated in Fig. 2. The usual lock nut 40 is provided for holding the stop screw 38 in any vertically adjusted position.

In applying the attachment the shipper rod is cut into the two sections 20 and 20 and holes are drilled for securing the brackets 25 and 39 in place. The upper shipper rod section is then drilled to receive the pins of the collar 26 and the sleeve 29, the lower shipper rod section notched and the attachment is then set up in the manner described.

In operation, when the operator presses on the treadle 2| the lower shipper rod section 20 is moved downwardly. Inasmuch as the dog 34 is held in engagement with the notch 3| by the spring 35 this downward movement is transmitted through this dog to the sleeve 29 and as this sleeve is pinned to the upper shipper rod section 29 this section is likewise moved downwardly and the clutch is closed so as to effect one complete reciprocation of the slide l3. As the operator continues the downward movement of the treadle 2! the tailpiece or finger 31 engages the upper end of the adjustable stop screw 38 which causes this finger 31 and the pin 33 to rotate and throw the dog 34 out of engagement with the notch 3|. As soon as this occurs the spring 21, reacting against the collar 26 forces the upper shipper rod section 2D upwardly so as to disengage the clutch when one revolution of the shaft 16 is completed, the clutches used with punch presses being of the type which insure complete revolutions of the drive shaft so that the slide I3 is always brought back to a normal elevated position. Any further downward movement of the treadle 2| is inoperative and the entire press is, of course, rendered inoperative for a repeated reciprocation of the slide l3 until the treadle is released whereupon the spring 23 elevates the treadle El and lower shipper rod section 20 so as to efiect a re-engagement of the pawl 34 and notch 3| preparatory to another operation of the punch press.

From the foregoing it will be seen that the present invention provides a very simple and efficient attachment which can be readily applied to punch presses of any standard form and which positively insures against automatic repeating operation of the punch press thereby rendering the punch press more safe in operation. It will also be appreciated that the attachment is capable of substantial modification within the scope of the appended claims and in particular can be reversed so as to operate in conjunction with a shipper rod which is pushed to close the clutch in contradistinction to the pull rod shown.

I claim as my invention:

1. A non-repeat attachment adapted to be interposed between two sections of the clutch operating rod of a punch press or the like, comprising a sleeve surrounding the opposing ends of both of said sections and forming a guide for one, a pin connecting said sleeve with the other section, a collar pinned to the section pinned to said sleeve, a latch carried by said sleeve and 0p- 5 erating through a slot in said sleeve to engage a notch in said unpinned section to compel said sections to move in unison, a stationary guide for the section pinned to said collar, a spring interposed between said collar and guide and working in opposition to said latch to effect relative movement of said sections when said latch is released and stop means for releasing said latch in response to movement of said sections in unison.

2. A non-repeat attachment adapted to be interposed between two sections of the clutch operating rod of a punch press or the like, comprising a sleeve surrounding the opposing ends of both of said sections and forming a guide for one and attached to the other rod section, a 001- lar attached to that section which is attached to said sleeve, a latch carried by said sleeve and operating through a slot in said sleeve to engage a notch in said unattached section to compel said sections to move in unison, a stationary guide for the section attached to said sleeve, a spring interposed between said collar and guide and working in opposition to said latch to effect relative movement of said sections when said latch is released, and stop means for releasing said latch in response to movement of said sections in unison.

3. A non-repeat attachment adapted to be interposed between two coaxial sections of the clutch operated rod of a punch press or the like, comprising a sleeve surrounding the opposing ends 35 of both of said sections and forming a guide for one and attached to the other section, an ear projecting laterally outward from said sleeve, a latch pivotally secured to said ear and operating through a slot in said sleeve to engage a notch in one side of said unattached section to compel said sections to move in unison, a spring arranged externally of said sleeve and interposed between said sleeve and one side of said latch and holding said latch in said notch, a main spring working in opposition to said latch to effect relative movement of said sections when said latch is released and stop means engaging the other side of said latch to release said latch in response to movement of said sections in unison.

4. A non-repeat attachment adapted to be interposed between two coaxial sections of the clutch operating rod of a punch press or the like, comprising a sleeve surrounding the opposing ends of both of said sections and forming a guide for one and attached to the other section, an ear projecting laterally outward from said sleeve, an L-shaped latch pivoted at its center to said ear and having one end operating through a slot in said sleeve to engage a notch in one side of said unattached section to compel said sections to move in unison, a second ear projecting outwardly from said sleeve, a spring interposed between the other end of said latch and said last mentioned ear and having its axis disposed parallel with said sections, and holding said latch in said notch, a main spring working in opposition to said latch to effect relative movement of said sections when said latch is released and stop means engaging that end of said latch which engages said first spring to release said latch in response to movement of said sections in unison.

EMIL SCHUESSLER. 

